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Biomedical subjects

S Kitagawa

Publications and source records attributed to S Kitagawa.

At least 253 records · Page 14Linked to original sources
PubMed1989

Validity of MR imaging for monitoring effects of percutaneous ethanol injection for HCC.

Magnetic resonance (MR) images of 44 hepato-cellular carcinoma (HCC) patients who had undergone percutaneous ethanol injection therapy (PEIT) were analyzed during and after the treatment. Using a long TE/TR spin-echo technique, the initial high intensity of the tumor decreased during treatment in all patients. Decrease in tumor intensity corresponded well with decrease of serum alpha-fetoprotein level and histopathological changes of the necrosis. During the long-term follow-up of three patients, the reappearance of a highly intense area was readily detected by MR imaging, and hence the recurrence of the tumor, as determined clinically or histopathologically, was confirmed. The long TE/TR spin-echo technique proves most helpful in monitoring the effectiveness of PEIT for HCC, as well as for its recurrence.

Carcinoma, Hepatocellular↗
PubMed1989

[A study of a regional lymph node metastasis in a well-differentiated thyroid carcinoma].

Forty-eight patients with a well-differentiated thyroid cancer that occupied unilateral lobe were given, a modified radical neck dissection (unilateral or bilateral). After an examination of their lymph nodes, a retrospective analysis showed that the metastasis extended to the lateral cervical lymph node on the ipsilateral neck in 43.8% of all cases, and to at least the paratracheal lymph node on the contralateral neck in 27.2% of all cases. Therefore a bilateral modified radical neck dissection is needed surgical treatment for such patients.

Adenocarcinoma↗
PubMed1989

[Macrophages and erythrocytes].

The mechanism by which senescent red blood cells (SRBCs) are eliminated from circulation by the reticuloendothelial system was investigated using the newly developed phagocytosis assay. Phagocytosis of SRBCs and Vibrio cholera neuraminidase (VCN) treated RBCs by autologous macrophages were significantly higher than that of unfractionated RBCs. The phagocytosis of VCN-treated RBCs was enhanced by pre-treatment of RBCs with freshly prepared autologous serum, but not with heat inactivated serum. These results suggest that the erythrophagocytosis is mediated by lectin-like receptors and complement receptors which are present on the surface of macrophages. We also studied the erythrophagocytic capacity of macrophages in the presence of tumor necrosis factor (TNF) as a model of the anemia due to acute inflammation. The phagocytosis of VCN-treated RBCs was enhanced with the addition of a small amount of TNF (1 U/ml). This result suggests that TNF enhances the destruction of damaged RBCs by activating the reticuloendothelial system.

Adult↗
PubMed1989

[Diagnosis of colon cancer (depth of invasion) by barium enema examination; present condition].

Accuracy of the barium enema examinations in diagnosis of the depth of invasion of the small carcinomas of the colon was reviewed. The materials included 101 sessile carcinomas and 12 small advanced carcinomas that were 20 mm or less in diameter. The carcinomas with stalks and the depressed type early carcinomas (Type IIc) were excluded from the study, because the former were impossible to the nature by X-ray examinations and the latter were extremely rare. Presence of the depressed portions on the surface of the elevated lesions observed in the frontal views and the degree of the deformity observed in the profile views of the lesions were correlated with the pathological specimen and the accuracy of the radiological diagnosis of the depth of invasion was estimated. The cases with gross malignant cell invasion into the submucosal or the deeper layers were diagnosed correctly with present radiological diagnostic criteria. But, those with a small amount of malignant cell invasion into the submucosal layer or the cases with malignant cell invasion limited to the mucosal layer (intramural cancer) were not always correctly diagnosed and there was a variety in diagnosis of the depth of invasion in this group. With the current radiological techniques, proper profile views of the lesions were not obtained in quite a few cases, nor the surface characteristics of the small elevated lesions were well documented. It would probably be possible to improve these techniques and to improve diagnostic accuracy to some extent, but with certain limitations.

Barium Sulfate↗
PubMed1989

[Yersinia enterocolitis--report of two cases].

We reported two cases of terminal ileitis caused by Yersinia enterocolitica (Y.e.). Y.e. was proven by stool culture in each case. They were admitted to the hospital complaining abdominal pain. They are examined by X-ray and endoscopy in the different time, and their examination revealed edema, coarse mucosa and varioliform elevated lesions with the passage of time.

Adult↗
PubMed1988

Property of class I H-2 alloantigen-reactive Lyt-2+ helper T cell subset. Abrogation of its proliferative and IL-2-producing capacities by intravenous injection of class I H-2-disparate allogeneic cells.

The present study investigates the distinctiveness of Class I H-2 alloantigen-reactive Lyt-2+ helper/proliferative T cell subset in the aspect of tolerance induction. Primary mixed lymphocyte reactions (MLR) revealed that Lyt-2+ and L3T4+ T cell subsets from C57BL/6 (B6) mice were exclusively capable of responding to class I H-2 [B6-C-H-2bm1 (bm1)]- and class II H-2 [B6-C-H-2bm12 (bm12)]-alloantigens, respectively. Anti-bm12 MLR was not affected by i.v. injection of bm12 spleen cells into recipient B6 mice. In contrast, a single i.v. administration of bm1 spleen cells into B6 mice resulted in the abrogation of the capacity of recipient B6 spleen and lymph node cells to give anti-bm1 MLR. This suppression was bm1 alloantigen-specific, since lymphoid cells from B6 mice i.v. presensitized with bm1 cells exhibited comparable anti-bm12 primary MLR to that obtained by normal B6 lymphoid cells. Such tolerance was rapidly (24 h after the i.v. injection of bm1 cells) inducible and lasting for at shortest 3 wk. Addition of lymphoid cells from anti-bm1-tolerant B6 mice to cultures of normal B6 lymphoid cells did not suppress the proliferative responses of the latter cells, indicating that the tolerance is not due to the induction of suppressor cells but attributed to the elimination or functional impairment of anti-bm1 proliferative clones. The tolerance was also demonstrated by the failure of tolerant lymphoid cells to produce IL-2. It was, however, found that anti-bm1 CTL responses were generated by tolerant lymphoid cells which were unable to induce the anti-bm1 MLR nor to produce detectable level of IL-2. These results demonstrate that class I H-2 alloantigen-reactive Lyt-2+ Th cell subset exhibits a distinct property which is expressed by neither Lyt-2+ CTL directed to class I H-2 nor L3T4+ Th cells to class II H-2 alloantigens.

Animals↗
PubMed1988

Phorbol myristate acetate potentiates superoxide release and membrane depolarization without affecting an increase in cytoplasmic free calcium in human granulocytes stimulated by the chemotactic peptide, lectins and the calcium ionophore.

We investigated the inter-relationships of superoxide (O2-) release, membrane depolarization and an increase in cytoplasmic free Ca2+, [Ca2+]i, in human granulocytes stimulated by various agonists. When concanavalin A or the Ca2+ ionophore ionomycin was used as stimulus, an increase in [Ca2+]i clearly preceded the onset of membrane depolarization, which was followed by O2- release. On the other hand, when N-formylmethionylleucylphenylalanine or wheat-germ agglutinin was used as stimulus, no demonstrable lag was seen in any of the responses. O2- release and membrane depolarization stimulated by all these agonists were markedly potentiated in parallel by pretreatment of cells with a low concentration of phorbol myristate acetate (0.25 ng/ml), whereas an increase in [Ca2+]i was not affected or minimally potentiated. The lag time between addition of the stimulus (concanavalin A or ionomycin) and onset of membrane depolarization or O2- release was significantly reduced by pretreatment of cells with phorbol myristate acetate, whereas the lag time between addition of concanavalin A and onset of the increase in [Ca2+]i was not affected. The dose-response curves for triggering of O2- release and membrane depolarization by each of receptor-mediated agonists in phorbol myristate acetate-pretreated or control cells were identical. These findings suggest that; (a) an increase in [Ca2+]i stimulates membrane depolarization indirectly; (b) a low concentration of phorbol myristate acetate potentiates membrane depolarization and O2- release by acting primarily at the post-receptor level, in particular, at the level distal to an increase in [Ca2+]i, but not by augmenting an increase in [Ca2+]i; and (c) the system provoking membrane depolarization and the system activating NADPH oxidase share a common pathway, which may be susceptible to a low concentration of phorbol myristate acetate.

Calcium↗
PubMed1988

Neolacto-series gangliosides induce granulocytic differentiation of human promyelocytic leukemia cell line HL-60.

Neolacto-series gangliosides having linear poly-N-acetyl-lactosaminyl oligosaccharide structure have been demonstrated to be increased characteristically during granulocytic differentiation of human promyelocytic leukemia cell line HL-60 cells induced by dimethyl sulfoxide or retinoic acid (Nojiri, H., Takaku, F., Tetsuka, T., Motoyoshi, K., Miura, Y., and Saito, M. (1984) Blood 64, 534-541). When HL-60 cells were cultured in the presence of neolacto-series gangliosides prepared from mature granulocytes, the cells were found to be differentiated into mature granulocytes on the basis of the changes of morphology, surface membrane antigens, nonspecific esterase activity, and the activity of phagocytosis and respiratory burst. The differentiation of cells was dependent on the concentration of gangliosides and accompanied with inhibition of cell growth. These findings suggest that the particular ganglioside molecules play an important role in regulation of cell differentiation and that the appearance of neolacto-series gangliosides on cell surface membrane not only triggers the differentiation but also determines the direction of differentiation in HL-60 cells.

Adult↗
PubMed1988

Thyroid hormone down-regulates p55, a thyroid hormone-binding protein that is homologous to protein disulfide isomerase and the beta-subunit of prolyl-4-hydroxylase.

We have previously characterized a cellular thyroid hormone-binding protein (p55) that is found concentrated on the lumenal face of the endoplasmic reticulum and nuclear envelope (Cheng, S.-y., Hasumura, S., Willingham, M.C., and Pastan, I. (1986) Proc. Natl. Acad. Sci. U.S.A. 83, 947-951). To understand the role p55 plays in thyroid hormone action, we examined the regulation of p55 by 3,3',5-triiodo-L-thyronine (T3). Rat pituitary tumor GH3 cells cultured in regular medium, thyroid hormone-depleted medium (Td medium), or Td medium supplemented with 50 nM T3 (Td + T3 medium) were metabolically labeled with [35S]methionine and immunoprecipitated with antibodies against p55. Treatment with T3 caused a fall in p55 levels. Poly(A+) RNA from cells cultured in regular, Td, or Td + T3 medium was hybridized to a cDNA from p55. T3 withdrawal or addition had no effect on p55 mRNA levels. Furthermore, the initial rates of synthesis of p55 from cells cultured in regular, Td, and Td + T3 were found to be similar. However, analysis of the decay curves from cells in which p55 was pulse-labeled with [35S]methionine indicated that p55 is 2-fold less stable in T3 containing medium. These results indicated that down-regulation of p55 by T3 occurs at the post-translational level. Since DNA sequence analysis indicates that p55 is identical to protein disulfide isomerase and the beta-subunit of prolyl-4-hydroxylase, T3 may mediate its effects on the synthesis, secretion, and/or transport of proteins via p55.

Animals↗
PubMed1988

Clinical application of phorbol diester-induced leukemic cell differentiation for the definite diagnosis of acute leukemias.

Seventy-three patients with acute leukemias or chronic myelogenous leukemias in blast crisis were evaluated as to the susceptibility of their leukemic cells to differentiation induction by a chemical agent, 12-O-tetradecanoyl phorbol-13-acetate (TPA). Leukemic cells of myeloid origin treated with TPA showed monocyte-macrophage-lineage differentiation morphologically and functionally, whereas those of lymphoid origin did not. We applied these differentiation phenomena for the clinical diagnosis of three leukemia cases in whom it was difficult to determine whether the leukemic cells were of non-lymphoid or lymphoid origin, although all the regular diagnostic procedures available had been performed. We successfully diagnosed these three cases by utilizing the above differentiation phenomena. Furthermore, this technique was clinically beneficial as to the choice of adequate chemotherapy in each of these leukemia cases. These findings confirm that the responsiveness to TPA of leukemic cells is of clinical usefulness for the definite diagnosis of acute leukemias.

Acute Disease↗
PubMed1988

Villous tumor of the colon: correlation of histologic, macroscopic, and radiographic features.

Forty-six patients with villous or tubulovillous tumors of the colon were examined to study the correlation between histologic and macroscopic or radiographic features and to define more accurately villous tumors of the colon. There was good correlation between the histologic and macroscopic or radiographic features. As villous elements became more prominent on histologic studies, the macroscopic appearance was more villous and granular but less nodular on the surface. Reticular and/or granular patterns with a feathery margin were more frequently seen on radiographs in cases of dominant villous elements. The macroscopic and radiographic characteristics of villous tumor frequently appeared when villous elements composed over 75% of the whole tumor on histologic studies. The authors propose that villous tumor of the colon can be accurately diagnosed when villous elements compose over 75% of the tumor.

Adenoma↗